The geomagnetic field was inactive on
March 20. Solar
wind speed at SOHO ranged between 287 and 346 km/s. A high speed stream
associated with CH797 arrived early on March 21.

Solar flux at 20h UTC on 2.8 GHz was 72.7 (decreasing
9.8over the last solar rotation). The
average 90 day 10.7 flux at 1 AU was 73.7. The Potsdam WDC planetary A
index was 2 (STAR Ap - based on the mean of three hour interval ap
indices: 1.5). Three hour interval K indices: 00000000 (planetary),
11211210 (Boulder) - since March 9, 2017 Boulder
has been reporting
significantly higher values than comparable latitude magnetometers, the data is
unreliable and should be ignored.

The background x-ray flux is at the class A5 level.

At the time of counting spots (see image time), spots were
observed in 1 active region using 2K resolution (SN: 12) and in 1 active region
using
1K
resolution (SN: 11) SDO images on the visible solar disk.

A recurrent trans equatorial coronal hole (CH797) was
in an
Earth facing position on March 18-21. A recurrent trans equatorial extension
(CH798) of the southern polar coronal hole will likely rotate across the central
meridian on March 24-25.

The geomagnetic field is expected to be quiet to minor storm
on March 21-23 due to effects from CH797.

Coronal holes (1)

Coronal mass ejection (2)

M and X class flares (3)

1) Effects from a coronal hole could reach Earth within the
next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at Earth within 96 hours.
3) There is a possibility of either M or X class flares within the next 48
hours.

When available the active region map has a coronal hole polarity overlay
where red (pink) is negative and blue is positive.

Data for all numbered solar regions according to the Solar Region Summary
provided by NOAA/SWPC. Comments are my own, as is the STAR spot count (spots
observed at or inside a few hours before midnight) and data for regions not
numbered by SWPC or where SWPC has observed no spots. SWPC active region numbers
in the table below and in the active region map above are the historic SWPC/USAF
numbers.

1) Running average based on the daily 20:00 UTC observed solar flux value at
2800 MHz.
2A) Current impact on the monthly sunspot number based on the Boulder
(NOAA/SWPC) sunspot number (accumulated daily sunspots / month days).
2B)
Boulder SN current month average to date.
2C) STAR SDO 1K Wolf number 30 day
average.
3) Running average based on the quicklook and definitive Potsdam WDC ap
indices. Values in red are based on the definitive
international
GFZ Potsdam
WDC
ap indices.
4) Updated to new data set from WDC-SILSO on July 1, 2015

This report has been prepared by Jan
Alvestad. It is based on the analysis of data from whatever sources are
available at the time the report is prepared. All time references are to
Universal Time. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.